I'm trying to create (pretty unsuccessfully) to build a tapered wood joist family. I've got it set up to taper based on slope (type parameter for rise/run then atan function to get angle) but the way the element needs to be placed in elevation is based on the low end of the slope or the bottom of the bottom chord. The grand plan is to use this to frame a wood roof using the beam system tool (big spaces with members spaced at 2'-0" OC). The joists will actually be bidder designed so I only want to show a top and bottom chord, no need to model the web members. I could do it as a truss I guess but I'm afraid I'd have to attach each truss to the roof deck above to get the slope correct.
Here's the problem. How can I set the "top" of the element to be based on the low end of the top chord? The reason being that is the constant for these, not the high end. And with a beam system I can only effectively place it based on the "top" of the member or an offset from there.